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Biomedical subjects

N Aoki

Publications and source records attributed to N Aoki.

At least 127 records · Page 7Linked to original sources
PubMed1998

The functional role of B7 molecules on the induction of thymocyte activation and apoptosis.

To evaluate the role of B7 on thymocyte activation and apoptosis, we took advantage of TCR transgenic mice in which the majority of thymocytes express a uniform TCR that is specific for ovalbumin. We also prepared Chinese hamster ovary (CHO) cells expressing B7 and appropriate class II molecules. We found that the apoptosis of double-positive thymocytes by TCR-mediated signaling, which presumably represents negative selection, requires a costimulatory signal provided by B7-1 or B7-2. The requirement of B7-1 costimulation for the apoptosis of thymocytes does not change in either low or high antigenic peptide loading. We also demonstrated that two signals through TCR and CD28 augmented the proliferation of thymocytes, and the requirement of CD28-mediated signal by B7-1 or B7-2 for thymocyte proliferation became less evident when high doses of antigenic peptide were loaded, indicating that the intensity of TCR-mediated signal determines the requirement of B7-mediated second signal for thymocyte proliferation.

Animals↗
PubMed1998

Postoperative inflammatory reaction developing focal but severe brain edema. A possible complication of topical application of Biobond-soaked oxycellulose.

A 66-year-old female underwent uneventful removal of parasagittal meningioma. At surgery, a piece of Biobond-soaked oxycellulose was applied to the lateral wall of the superior sagittal sinus for hemostasis. Her early postoperative course was complicated by focal but severe brain edema, which was adjacent to the hemostatic agent. Unlike foreign body granuloma previously reported, this complication was considered to be attributed to inflammatory reaction of Biobond, because of the early onset and fulminant edema despite of small volume of the mass lesion. Although there have been no previous reports of this complication, it should be kept in mind that intracranial application of Biobond may induce fulminant inflammatory reaction as seen in this patient.

Acute-Phase Reaction↗
PubMed1998

Archetype JC virus efficiently replicates in COS-7 cells, simian cells constitutively expressing simian virus 40 T antigen.

JC polyomavirus (JCV), the causative agent of progressive multifocal leukoencephalopathy (PML), is ubiquitous in humans, infecting children asymptomatically and then persisting in the kidney. Renal JCV is not latent but replicates to excrete progeny in the urine. The renal-urinary JCV DNAs carry the archetype regulatory region that generates various rearranged regulatory regions occurring in JCVs derived from the brains of PML patients. Tissue cultures that support the efficient growth of archetype JCV have not been reported. We studied whether archetype JCV could replicate in COS-7 cells, simian cells transformed with an origin-defective mutant of simian virus 40 (SV40). Efficient JCV replication, as detected by a hemagglutination assay, was observed in cultures transfected with five of the six archetype DNAs. The progeny JCVs could be passaged to fresh COS-7 cells. However, when the parental cells of COS-7 not expressing T antigen were transfected with archetype JCV DNAs, no viral replication was detected, indicating that SV40 T antigen is essential for the growth of JCV in COS-7 cells. The archetype regulatory region was conserved during viral growth in COS-7 cells, although a small proportion of JCV DNAs underwent rearrangements outside the regulatory region. We then attempted to recover archetype JCV from urine by viral culture in COS-7 cells. Efficient JCV production was observed in COS-7 cells infected with five of the six JCV-positive urine samples examined. Thus, COS-7 cells should be of use not only for the production of archetype JCV on a large scale but also for the isolation of archetype JCV from urine.

Aged↗
PubMed1998

Clinical significance of hypoxemia without congestive heart failure in patients presenting with acute myocardial infarction.

This study investigated the clinical significance of hypoxemia without apparent clinical congestive heart failure in patients with acute myocardial infarction (AMI). Sixty-two patients with AMI of the Killip group I and Forrester subset I state were stratified into a hypoxemia group and a normoxemia group. The increase in the neutrophil count and the severity of the coronary artery disease as graded by Gensini's score were significantly higher in the hypoxemic group. The cardiac index was lower in hypoxemic than normoxemic patients. Myocardial scintigraphy revealed no acute difference in defect scores (DS) or left ventricular ejection fraction (LVEF) between the two groups, but DS was significantly higher (p < 0.01) and LVEF was lower (p < 0.01) in the hypoxemic group 2 years after infarction. Patients with hypoxemia have a more severe angiographic coronary pathology than normoxemic patients, and latent cardiac hypofunction occurs.

Adult↗
PubMed1998

Mechanism of rethrombosis after thrombolytic therapy: angioscopic findings and investigation of the coagulation system in dogs.

The purpose of this study was to angioscopically observe the process of thrombolysis after intracoronary administration of thrombolytic agents and to investigate the effects of these agents on coagulation/fibrinolysis systems in dogs. The coronary endothelium was removed and thrombus formation was confirmed by angioscopy. In the tissue plasminogen activator (tPA) group (n=8), complete thrombolysis occurred in all animals, but thrombolysis was incomplete in the urokinase (UK) group (n=6). The plasma level of plasmin alpha2-plasmin inhibitor complex peaked at 15 minutes after treatment in both the tPA and UK groups. Plasma thrombin-antithrombin III (TAT) complex decreased transiently at 15 minutes after tPA administration but increased at 30 and 60 minutes (P<0.05). In the UK group, plasma TAT also showed a transient decrease followed by an increase, which was minimal compared with that in the tPA group. Plasma TAT decreased transiently after infusion of tPA and subsequently increased to above the pretreatment level, suggesting a risk of rethrombosis after successful recanalization.

Angioscopy↗
PubMed1998

Plasma soluble P-selectin in acute myocardial infarction: effects of coronary recanalization therapy.

P-selectin is translocated from platelets and endothelial cells to initiate the first step in a sequence of events leading to the adherence of leukocytes, possibly inducing reperfusion injury and the no-reflow phenomenon in acute myocardial infarction (AMI). This study was undertaken to investigate plasma P-selectin in AMI patients undergoing coronary recanalization therapy. A total of 40 patients were studied: 20 patients with AMI who underwent coronary recanalization by direct percutaneous transluminal coronary angioplasty (PTCA), 10 patients with AMI who underwent thrombolytic therapy by tissue-type plasminogen activator (TPA), and 10 patients with stable angina pectoris who underwent elective PTCA. Blood samples were obtained from systemic arteries before and immediately after PTCA or thrombolytic therapy. Plasma-soluble P-selectin was measured by enzyme immunoassay. Plasma P-selectin was significantly higher in AMI than in stable angina pectoris (176.6 +/- 12.9 ng/mL vs 91.4 +/- 9.5 ng/mL, p<0.001). Plasma P-selectin did not change significantly as a result of elective PTCA in patients with stable angina (from 91.4 +/- 9.5 ng/mL to 87.9 +/- 7.9 ng/mL). Plasma P-selectin was decreased by direct PTCA in all of the 20 patients with AMI (from 176.2 +/- 17.7 ng/mL to 141.7 +/- 12.6 ng/mL; p<0.001, paired t-test), whereas it was increased by thrombolysis using TPA in nine of the 10 AMI patients (from 177.4 +/- 17.2 ng/mL to 248.8 +/- 17.3 ng/mL, p<0.005). Increased P-selectin activity in AMI appeared to be attenuated by direct PTCA, but augmented by thrombolysis, possibly due to direct stimulatory effects of TPA on P-selectin expression. This may lead to less favorable results in salvaging the ischemic myocardium by thrombolytic than mechanical coronary recanalization therapy in AMI.

Angina Pectoris↗
PubMed1998

Change of peripheral levels of pituitary hormones and cytokines after injection of interferon (IFN)-beta in patients with chronic hepatitis C.

Interferons (IFNs) are now in use worldwide for the treatment of chronic viral hepatitis. Unfortunately, various side effects of IFNs have been reported. Because cytokines, which include IFNs, can affect endocrine function, endocrinological abnormalities are sometimes observed in patients treated with IFNs. We examined the effects of IFN-beta on peripheral levels of pituitary and adrenal hormones and cytokines. Six million international units of IFN-beta dissolved in glucose solution was injected for 30 min. As a control study, glucose solution without IFN-beta was injected. Pituitary hormones (ACTH, GH, TSH, prolactin (PRL), LH, FSH, and arginine-vasopressin (AVP)), cortisol, and cytokines such as interleukin (IL)-1, IL-6, tumor necrosis factor-alpha (TNF), and interleukin-1 receptor antagonist (IL-1ra) were measured before and after IFN-beta injection. The study was carried out on 14 patients with chronic hepatitis type C who were under treatment with IFN-beta. All studies were performed when the patients were afebrile. None of the patients had any endocrine or autoimmune diseases. Plasma ACTH levels increased significantly at 60-120 min after IFN-beta injection compared with the levels before IFN-beta injection and in the control study using glucose injection. Plasma cortisol levels increased after IFN-beta injection, in parallel with plasma ACTH elevation. Serum GH levels increased significantly at 120 min after IFN-beta injection. All the increased hormones including ACTH, cortisol, and GH, were decreased at the end of the study-180 min after IFN-beta injection. Serum levels of TSH, PRL, LH, FSH, and AVP were not changed significantly by IFN-beta injection. Plasma IL-1 and TNF levels did not change after IFN-beta injection, while IL-6 and IL-1ra were elevated significantly. The increases in IL-6 and IL-1ra were gradual, reaching their peak levels at 180 min after IFN-beta injection. However there were no correlations between the hormones measured in this study and the levels of IL-6 or IL-1ra. It would seem that IFN-beta has direct or indirect stimulatory effects for ACTH and GH without mediation of the cytokines. These in vivo results are important for investigating the relationship between endocrine and cytokine systems in humans.

Adrenal Cortex Hormones↗
PubMed1998

Evaluation of potential fat emboli during placement of intramedullary nails after orthopedic fractures.

STUDY OBJECTIVE: To evaluate material with high echogenicity demonstrated by transesophageal echocardiography (TEE) during the reamed intramedullary nailing procedure in long-bone fracture patients, and to analyze BAL fluid (BALF) in these patients as well as in those with the fat embolism syndrome (FES). DESIGN: Prospective cohort study. SETTING: Emergency and critical care center of a university hospital. PATIENTS: Fifteen patients with long-bone fractures in whom reamed intramedullary nailing was performed, and five patients diagnosed with FES. MEASUREMENTS: During reamed nailing procedures, TEE was performed. We measured the differential cell counts, percentage of lipid-laden cells, and albumin concentration in BALF after the operation. We compared TEE findings and BALF analysis in the surgical patients. In addition, we compared BALF findings in the surgical patients and in the FES patients. RESULTS: We divided 15 patients who underwent TEE into three subtypes based on the appearance of embolic material within the chambers of the right heart. The lipid-laden cells in BALF increased significantly in those patients with highly echogenic material by TEE (p < 0.05). The percentage of the lipid-laden cells in BALF was not significantly different between the TEE patients and those with FES. On the other hand, FES patients showed a statistically significant increase in leukocyte counts and albumin concentration (p < 0.05). CONCLUSIONS: The highly echogenic material seen in TEE during reamed intramedullary nailing could be fat globules on the basis of BALF analysis. However, all patients with large emboli by TEE do not develop FES. A factor other than mechanical obstruction by fat globules may be necessary for the development of FES.

Adolescent↗
PubMed1998

[Study on abuse and neglect of the disabled elderly living at home].

To obtain basic information on elderly abuse and neglect in order to provide for its early discovery and prevention, a questionnaire survey about the present situation regarding abuse and neglect of the disabled elderly living at home was performed on health/medical service/welfare professions. Forty-two cases were analyzed. The major results were as follows; 1. Victims were 13 men and 29 women, approximately 1/3 of whom were in their 70's and another 1/3 in their 80's. Approximately 1/4 of the abusers were either sons or daughters of the victims. 2. Verbal abuse was the most frequent type of abuse with a rate of 69.0%. The percentage of psychological abuse was 61.9, passive neglect was 57.1%, active neglect was 50.0%, physical abuse was 47.6%, passive self-neglect was 28.6%, financial/material exploitation was 23.8%, active self-neglect was 16.7% and the others was 11.9%. The average number of abuse and neglect that an elderly received was 3.5. 3. The main causes of abuse and neglect did not appear to be simple but was complicated by related causes, many of both victims and abusers had elements in their personality, developmental history and interpersonal relationships that over a period of years formed the basis for the problematic behavior. Many abuse or neglect cases arose from caregiving burden of family caregivers or insufficient social systems for support to meet the needs of caring for the elderly. 4. The results suggest that for prevention and countermeasures for elderly abuse, there is an urgent need to arrange for expansion of health and welfare services to reduce burden of caregivers, provide for education of professionals of health/medical service/welfare for early discovery and proper handling of abuse problems, development of a checklist for early discovery, expansion of opportunities of improving care skill for family caregivers and establishment of consultation system for the elderly and caregivers, and organizing emergency shelter for victims of elderly abuse.

Aged↗
PubMed1998

[Susceptibilities of bacteria isolated from patients with lower respiratory infectious diseases to antibiotics (1996)].

The bacteria isolated from the patients with lower respiratory tract infections were collected by institutions located throughout Japan, since 1981. Ikemoto et al. have been investigating susceptibilities of these isolates to various antibacterial agents and antibiotics, and characteristics of the patients and isolates from them each year. Results obtained from these investigations are discussed. In 16 institutions around the entire Japan, 557 strains of presumably etiological bacteria were isolated mainly from the sputa of 449 patients with lower respiratory tract infections during the period from October 1996 to September 1997. MICs of various antibacterial agents and antibiotics were determined against 98 strains of Staphylococcus aureus, 93 strains of Streptococcus pneumoniae, 84 strains of Haemophilus influenzae, 84 strains of Pseudomonas aeruginosa (non-mucoid strains), 17 strains of Pseudomonas aeruginosa (mucoid strains), 31 strains of Moraxella subgenus Branhamella catarrhalis, 21 strains of Klebsiella pneumoniae etc., and the drug susceptibilities of these strains were assessed except for those strains that died during transportation. 1) S. aureus S. aureus strains for which MICs of oxacillin (MPIPC) were higher than 4 micrograms/ml (methicillin-resistant S. aureus) accounted for 67.3%. The frequency of the drug resistant bacteria increased comparing to the previous year's 52.7%. Arbekacin (ABK) and vancomycin (VCM) showed the highest activities against both S. aureus and MRSA with MIC80s of 1 microgram/ml. 2) S. pneumoniae Imipenem (IPM) and panipenem (PAPM) of carbapenems showed the most potent activities with MIC80s of 0.063 microgram/ml. Faropenem (FRPM) showed the next potent activity with MIC80 of 0.125 microgram/ml. The other drugs except erythromycin (EM), clindamycin (CLDM) and tetracycline (TC) were active against S. pneumoniae tested with MIC80s of 8 micrograms/ml or below. 3) H. influenzae The activities of all drugs were potent against H. influenzae tested with MIC80s of 4 micrograms/ml or below. Cefotiam (CTM), cefmenoxime (CMX), cefditoren (CDTR) and ofloxacin (OFLX) showed the most potent activities with MIC80s of 0.063 microgram/ml. 4) P. aeruginosa (mucoid strains) Tobramycin (TOB) showed the most potent activity against P. aeruginosa (mucoid strains) with MIC80 of 1 microgram/ml. Ceftazidime (CAZ), cefsulodin (CFS), IPM, gentamicin (GM), ABK and ciprofloxacin (CPFX) showed the next potent activities, with MIC80s of 2 micrograms/ml. The MIC80s of the other drugs ranged from 4 micrograms/ml to 16 micrograms/ml. 5) P. aeruginosa (non-mucoid strains) TOB and CPFX showed the most potent activities against P. aeruginosa (non-mucoid strains) with MIC80s of 1 microgram/ml. The MIC80s of piperacillin (PIPC) and cefoperazone (CPZ) were 16 micrograms/ml in 1995, and they were 64 micrograms/ml in 1996. 6) K. pneumoniae All drugs except ampicillin (ABPC) were active against K. pneumoniae. CMX, cefpirome (CPR), cefozopran (CZOP) and carumonam (CRMN) showed the most potent activities against K. pneumoniae with MIC80s of 0.125 microgram/ml. The MIC80s of the other drugs ranged from 0.25 microgram/ml to 2 micrograms/ml. 7) M.(B) catarrhalis Against M.(B.) catarrhalis, all drugs showed good activities with MICs of 4 micrograms/ml or below. IPM and minocycline (MINO) showed the most potent activities with MICs of 0.063 microgram/ml. Also, we investigated year to year changes in the characteristics of patients, their respiratory infectious diseases, and the etiology. Patients' backgrounds were examined for 557 isolates from 449 cases. The examination of age distribution indicated that the proportion of patients with ages over 60 years was 71.0% of all the patients showing a slight increase over that in 1994. Proportions of diagnosed diseases were as follows: Bacterial pneumonia and chronic bronchitis were the most frequent with 35.9% and 30.3% respectively. They were followed by bronchiectasis with a proportion of 10.

Adult↗
PubMed1998

[Assessment of global and regional LV function obtained by quantitative gated SPECT using 99mTc-tetrofosmin: comparison with left ventricular cineangiography and echocardiography].

The quantitative gated SPECT (QGS) software that has automatic edge detection algorithm of the left ventricle, is able to calculate LV volumes and visualize LV wall motion with perfusion throughout the cardiac cycle. We evaluated the reliability of global and regional LV function derived from QGS using 99mTc-tetrofosmin by comparing with left ventricular cineangiography (LVG) and echocardiography (ECHO). In 22 cardiac patients, end-diastolic volume (EDV), end-systolic volume (ESV) and ejection fraction (LVEF) were calculated. Using cinematic display, regional LV wall motion were scored on a 3-point scale (1 = normal, 2 = hypokinesis, 3 = akinesis; WMS). EDV, ESV and LVEF correlated well with those by LVG (p < 0.001 for each). Correlation between WMS derived from QGS and ECHO was high (r = 0.85, p < 0.001). There was an inverse correlation between WMS and LVEF (r = 0.77, p < 0.001). In conclusion, QGS is useful to evaluate global LV function. Regional wall motion evaluated by QGS is good enough for clinical application.

Cineangiography↗
PubMed1997

Isolation and characterization of mouse high-glycine/tyrosine proteins.

During hair follicle differentiation, several families of keratin proteins are synthesized sequentially. In the present study, cDNA clones encoding six members of mouse high-glycine/tyrosine protein were isolated by screening a cDNA library prepared from the mouse skin of an anagen phase with a differential hybridization technique. On the basis of their nucleotide and deduced amino acid sequences, they were found to encode two members of high-glycine/tyrosine protein type I and four of type II. Interestingly, one of the four type II proteins had been encoded by two distinct cDNAs. Among the cDNA clones isolated were included the ones encoding a new member of type I and II protein, respectively, which possessed an entire open reading frame. Novel type II protein, termed type II.4, with a molecular mass of 15,130 Da was revealed to have significant direct repeats and a cysteine residue at the carboxyl terminus, which indicates that this protein has characteristics intermediate between high-glycine/tyrosine proteins and cysteine-rich proteins. In addition, the new member of type I protein has some features common with type II protein. We propose to term this protein type Ialpha until it is further characterized. Northern blot analysis demonstrated that gene expression of mouse high-glycine/tyrosine proteins followed the hair cycle growth fundamentally and reached its peak at day 9 in the first hair cycle, while two peaks of their expression were observed at day 33 and day 39 in the second cycle. Their transcripts were expressed in the cortical cells of hair follicles but not in the cells of the outer root sheath, inner root sheath, or medulla. Moreover, their gene expression commenced at different levels in cortical cells. The novel findings that each gene is activated transcriptionally with a distinct expression pattern spatially and temporally suggest that there is a remarkable difference in the distribution of these proteins in hair.

Amino Acid Sequence↗
PubMed1997

Coronary artery disease and polymorphisms in a receptor mediating shear stress-dependent platelet activation.

BACKGROUND: Platelets play pivotal roles in coronary thrombosis, and antiplatelet therapies are widely used for coronary artery disease (CAD). However, the effects of genetic variation in platelets on CAD are poorly understood. We have assessed the association between CAD and polymorphisms in a platelet receptor for von Willebrand factor, the glycoprotein (GP) Ib/IX complex, which mediates shear stress-dependent platelet activation. METHODS AND RESULTS: Genotypes of the alpha-chain of the receptor (GP Ib alpha, 145Thr/Met) were determined in 91 patients with myocardial infarction (MI) or angina pectoris whose lesions were confirmed by coronary angiography as well as in 105 individuals from the general population with no history of angina or other heart diseases and normal resting ECGs. There was no homozygote for Met/Met in either the control or patient groups. The prevalence of the Thr/Met genotype (T/M) in all patients was not significantly different from that in the control group. However, the frequency of T/M was significantly higher in patients aged < or = 60 years (31.8%) than in control subjects aged < or = 60 years (16.0%; P<.05, odds ratio=2.5). An association was also demonstrated between CAD and the other polymorphism of GP Ib alpha, a variable number of tandem repeats of a 13-amino acid sequence, which is known to be linked to the 145Thr/Met polymorphism. There was an association between the frequency of the T/M genotype and the angiographic severity of CAD: 11.1% for Gensini score < 40 versus 50.0% for Gensini score > or = 40 (P=.0015). There was no difference in the distribution of GP Ib alpha genotypes between patients with MI and those with angina pectoris. CONCLUSIONS: This study suggests that the presence of the Met allele in GP Ib alpha is a risk factor for the prevalence and severity of CAD in individuals aged < or = 60 years. The results need to be confirmed in a large-scale study of incident case subjects and matching control subjects.

Adult↗
PubMed1997

Critical role of calcium- dependent epidermal growth factor receptor transactivation in PC12 cell membrane depolarization and bradykinin signaling.

PC12 cells respond to a variety of external stimuli such as growth factors, neurotransmitters, and membrane depolarization by activating the Ras/mitogen-activated protein kinase pathway. Here we demonstrate that both depolarization-induced calcium influx and treatment with bradykinin stimulate tyrosine phosphorylation of the epidermal growth factor receptor (EGFR). Using a tetracycline-controlled expression system in conjunction with a dominant-negative EGFR mutant, we demonstrate that depolarization and bradykinin triggered signals involve EGFR function upstream of SHC and MAP kinase. Furthermore, bradykinin-stimulated EGFR transactivation is critically dependent on the presence of extracellular calcium, and when triggered by ionophore treatment, calcium influx is already sufficient to induce EGFR tyrosine phosphorylation. Taken together, our results establish calcium-dependent EGFR transactivation as a signaling mechanism mediating activation of the Ras/mitogen-activated protein kinase pathway in neuronal cell types.

Animals↗
PubMed1997

Aspartate-474 in the first exoplasmic loop of the thyrotropin receptor is crucial for receptor activation.

Asp-474 in the first exoplasmic loop of the thyrotropin receptor (TSHR), which is conserved among all glycoprotein hormone receptors, was mutated to Glu which is similarly charged but is longer by one methylene group and expressed in Cos-7 cells. Cells expressing this mutant receptor showed markedly impaired TSH- and TSAb (thyroid stimulating antibody)-stimulated cAMP responses with no effect on TSH binding affinity when compared with cells expressing a similar number of wild-type receptors. These results suggest the importance of Asp-474 in TSHR in receptor activation as demonstrated for LHR (lutropin receptor), but this, unlike LHR, is not due to the electrostatic interaction of this Asp residue with the alpha-subunit Lys-91 of the hormone.

Animals↗
PubMed1997

Stage specific expression of milk fat globule membrane glycoproteins in mouse mammary gland: comparison of MFG-E8, butyrophilin, and CD36 with a major milk protein, beta-casein.

The expression of mouse milk fat globule membrane (MFGM) glycoproteins, MFG-E8, butyrophilin, CD36 was analyzed by Northern blot analyses. MFG-E8 and butyrophilin mRNAs were specifically detected in the mammary gland of lactating mice, whereas CD36 mRNA was detected in the heart and lung as well as in the mammary gland of lactating mice. The mRNAs of the three MFGM glycoproteins accumulated at mid-lactation were about 2-10-times as much as those of the early and late gestation stages, whereas beta-casein mRNA accumulation was dramatically increased; the mRNA at mid-lactation was no less than 40-times as much as that before lactation. In mouse mammary epithelial cell lines, HC11 and COMMA-1D, only a slight or almost no enhancement for the expression of MFG-E8, butyrophilin and CD36 mRNAs was induced simply by the treatment with the lactogenic hormones such as prolactin, insulin and dexamethasone, whereas the beta-casein mRNA expression was remarkably enhanced only by that treatment. Furthermore, while the beta-casein protein was constantly detected in milk throughout the lactation stage, the content of MFG-E8 and butyrophilin proteins increased during the lactation with an increase in the milk fat content. These results suggest that the stage-specific expression of milk fat globule membrane glycoproteins in mammary epithelial cells is regulated in a similar but not necessarily identical mechanism to that of a major milk protein, beta-casein.

Animals↗
PubMed1997

Species-specific beta-N-acetylgalactosaminylation of serum IgG proteins.

Lectin blot analysis of bovine, goat, human, rabbit and mouse serum immunoglobulin G (IgG) samples revealed that Wisteria floribunda agglutinin (WFA) binds to the heavy chains of bovine, goat and human serum IgG proteins but not those of the rabbit and mouse proteins. WFA-positive light chain bands were also detected in bovine, goat and human serum IgG samples only after the filters were treated with Arthrobacter ureafaciens sialidase. The WFA-binding to these IgG proteins was abolished by treatment of the filter with sialidase and then beta-N-acetylhexosaminidase or N-glycanase prior to incubation with the lectin. WFA-agarose column chromatography of the oligosaccharides released by hydrazinolysis from the IgG samples followed by reduction with NaB3H4 revealed that 0.15, 0.09 and 0.07% of the total oligosaccharides from bovine, goat and human serum IgG samples bind to the column, respectively. Partial characterization of WFA-positive bovine IgG oligosaccharides by Bio-Gel P-4 column chromatography suggested that the major oligosaccharide is of non-fucosylated biantennary complex-type. These results indicate that beta-N-acetylgalactosaminylation occurs to N-linked sugar chains of heavy and light chains of IgG proteins in a species-specific manner.

Animals↗